President Yoon Suk Yeol and King Charles III celebrated the 140th anniversary of the two countries' diplomatic relationship in a series of high-profile events held in London on Tuesday, pledging to set new milestones for their bilateral ties as well as to join hands to promote freedom, peace and prosperity worldwide.

Tuesday's grand ceremonial welcome celebrated the centuries-old friendship between South Korea, which rose from the ashes of the Korean War to becoming Asia's fourth-largest economy, and the UK, South Korea's first diplomatic partner among the European countries, which later sent troops to fight for the South's freedom and democracy during the 1950-53 Korean War.

Yoon, the first foreign leader to make a state visit to the UK since King Charles' coronation in April, paid respect to the fallen heroes of the UK and expressed gratitude to veterans of the Korean War. At the same time, Yoon stressed that the UK would work with Korea to boost the security and economy of the Indo-Pacific region, amid ongoing military conflicts in Ukraine and the Middle East, as well as to address provocations from North Korea, including Wednesday's spy satellite launch.

Recalling the stories of rank-and-file soldier Bill Speakman, who won the Victoria Cross for his courageous actions in the Korean War, and James Logan, who was killed during the Battle of the Imjin River, Yoon said the "blood brotherhood" between South Korea and the UK is a clear indication that "there is nothing we can't do together for the future" in his opening remarks at the state banquet in the evening given by King Charles at Buckingham Palace.

The banquet had some 180 participants from South Korea and the UK, including K-pop group Blackpink.

Earlier on Tuesday, Yoon and first lady Kim Keon Hee received the full royal treatment to begin the day. Following a 41-gun salute, Yoon and King Charles inspected rows of troops from the Scots Guards, before joining King Charles and Queen Camilla in a carriage procession of seven horse-drawn coaches along the Mall to Buckingham Palace, followed by lunch at the palace and a tour of items from the Royal Collection related to South Korea.

Yoon went on to attend a wreath-laying ceremony at the Korean War Memorial in Victoria Embankment Gardens in London and visit the Grave of the Unknown Warrior in Westminster Abbey. He wrote in the Westminster Abbey guestbook: "Your dedication to freedom and justice will be remembered forever."

Later Tuesday, Yoon addressed both houses of Parliament in London, urging the United Kingdom to work jointly to overcome challenges in the Indo-Pacific region.

"(South Korea) will work with the United Kingdom to bolster the political and economic security in the Indo-Pacific region," Yoon told the House of Commons during his English-language speech. It was Yoon's second address to an overseas legislature to be delivered in English, after an address in April before the US Congress in Washington.

"Together, we will build a free and open international order. Together, we will cultivate sustainable growth and prosperity for all of humanity," he added.

Yoon highlighted UK forces' participation in the combined military exercise of South Korea and the United States for the first time earlier this year. Some 40 soldiers of the UK's Royal Marines Commandos took part in April in the Ssangyong Exercise, a regular amphibious landing exercise of the US and South Korea Navy and Marine Corps.

"(South Korea and the UK) will tackle North Korea’s WMD threats," Yoon said, referring to North Korea's weapons of mass destruction.

"We will work more closely together to combat international cybercrimes including cryptocurrency theft and technology hacking."

Calling the UK the birthplace of liberal democracy and market capitalism, Yoon thanked the UK for its support in South Korea's fight against communism and in its efforts to rise from the ashes of the Korean War to strive for freedom, democracy and economic prosperity.

Over 80,000 UK troops, including 56,000 in a combat role, were sent to the Korean War under the United Nations flag, making the UK contingent the second-largest after that of the United States. Nearly 1,200 UK soldiers were killed during the war.

"One country alone cannot defend peace," Yoon said.

"Korea stands united with the United Kingdom and the international community to fight against illegal aggression and provocations. We will uphold established norms and international order," Yoon continued.

On the economic front, Yoon vowed to modernize its trade pact with the UK, which took effect in 2021. South Korea was the first Asian country to sign a post-Brexit trade deal with the UK. The UK was South Korea's 16th-largest trade partner, with trade volume of some 18 billion pounds ($22.5 billion) last year.

Yoon also asked London to work together to shape new norms in the digital era in the face of challenges to freedom and democracy the new age presents, while expressing appreciation for UK Prime Minister Rishi Sunak's role in the success of the AI Summit at Bletchley Park, a site 80 kilometers northwest of London, earlier in November.

Meanwhile, negotiations are to kick off later during his state visit to the UK to broaden cooperation in the digital, artificial intelligence, cybersecurity, nuclear energy and defense industries. Talks will also include the bio, space, semiconductors, offshore wind, green energy and maritime sectors, he added.

The address came along with the speech by Lindsay Hoyle, speaker of the House of Commons, where he praised South Korea's transition from recipient of aid to donor over 70 years, as well as its announcement of a $2 billion aid commitment for Ukraine during the Group of 20 summit in New Delhi, India in September.

"International cooperation secured democracy, prosperity and freedom. But the Republic of Korea continues to exist in the shadow of a totalitarian regime," Hoyle said.

"Given this history, it is no surprise that your country, Mr. President, has offered staunch support to Ukraine, a country which faces a battle for its very survival, its freedom and its way of life, just as the Republic of Korea did over 70 years ago."